Prosecution Insights
Last updated: April 19, 2026
Application No. 18/578,539

BRUSHLESS MOTOR

Non-Final OA §103§DP
Filed
Jan 11, 2024
Examiner
MOK, ALEX W
Art Unit
2834
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Dyson Technology Limited
OA Round
1 (Non-Final)
74%
Grant Probability
Favorable
1-2
OA Rounds
2y 11m
To Grant
95%
With Interview

Examiner Intelligence

Grants 74% — above average
74%
Career Allow Rate
827 granted / 1114 resolved
+6.2% vs TC avg
Strong +21% interview lift
Without
With
+21.2%
Interview Lift
resolved cases with interview
Typical timeline
2y 11m
Avg Prosecution
44 currently pending
Career history
1158
Total Applications
across all art units

Statute-Specific Performance

§101
1.2%
-38.8% vs TC avg
§103
63.6%
+23.6% vs TC avg
§102
26.1%
-13.9% vs TC avg
§112
7.1%
-32.9% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1114 resolved cases

Office Action

§103 §DP
DETAILED ACTION Notice of Pre-AIA or AIA Status The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . Double Patenting The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969). A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b). The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13. The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer. Claims 1-9, 12, and 13 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 4-10, 13, and 14 of copending Application No. 18/578,424 (reference application). Although the claims at issue are not identical, they are not patentably distinct from each other because: For claim 1, claim 4/1 of copending application 18/578,424 disclose a stator assembly (see claim 4/1 of copending application 18/578,424), and a frame within which the stator assembly is housed (see claim 4/1 of copending application 18/578,424), wherein the frame is overmoulded to the stator assembly (see claim 4/1 of copending application 18/578,424); and wherein the frame comprises a plurality of turbulators (see claim 4/1 of copending application 18/578,424). For claim 2, claim 5/4/1 of copending application 18/578,424 disclose the turbulators being formed during a process of over-moulding the frame to the stator assembly (see claim 5/4/1 of copending application 18/578,424). For claim 3, claim 1 of copending application 18/578,424 disclose the stator assembly comprising a plurality of stator core sub-assemblies a bobbin attached to the stator core (see claim 1 of copending application 18/578,424), and a winding wound about the bobbin (see claim 1 of copending application 18/578,424), each stator core comprising a back and first and second arms extending from the back (see claim 1 of copending application 18/578,424). For claim 4, claim 1 of copending application 18/578,424 disclose the frame being overmoulded to stator assembly such that the back of the first and second arms of each stator core is exposed through the frame (see claim 1 of copending application 18/578,424). For claim 5, claim 6/4/1 of copending application 18/578,424 disclose the plurality of turbulators overlie the backs of the stator cores (see claim 6/4/1 of copending application 18/578,424). For claim 6, claim 7/4/1 of copending application 18/578,424 disclose the plurality of turbulators being obliquely angled relative to an axis substantially parallel to a central longitudinal axis of the brushless motor (see claim 7/4/1 of copending application 18/578,424). For claim 7, claim 8/7/4/1 of copending application 18/578,424 disclose the plurality of turbulators being angled between 45-75 degrees relative to the axis (see claim 8/7/4/1 of copending application 18/578,424). For claim 8, claim 9/8/7/4/1 of copending application 18/578,424 disclose the plurality of turbulators being angled at around 60 degrees relative to the axis (see claim 9/8/7/4/1 of copending application 18/578,424). For claim 9, claim 10/7/4/1 of copending application 18/578,424 disclose the trailing end of each turbulator being closer to the axis than a leading end of the turbulator (see claim 10/7/4/1 of copending application 18/578,424). For claim 12, claim 13/4/1 of copending application 18/578,424 disclose a height of each turbulator being in the region of 0.3-0.9 mm (see claim 13/4/1 of copending application 18/578,424). For claim 13, claim 14/4/1 of copending application 18/578,424 disclose the plurality of turbulators comprising a plurality of pairs of turbulators (see claim 14/4/1 of copending application 18/578,424), each pair of turbulators arranged in a generally V-shaped formation (see claim 14/4/1 of copending application 18/578,424). This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented. Claim Rejections - 35 USC § 103 In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status. The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. Claim(s) 1, 2, and 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. (US Patent Application Pub. No.: US 2013/0221889 A1) in view of Lau et al. (US Patent Application Pub. No.: US 2013/0229071 A1). For claim 1, Kim et al. disclose the claimed invention comprising a stator assembly (reference numerals 100a, 100b, 100c, figures 1A, 1B), and a frame (reference numeral 140) within which the stator assembly is housed (see figures 1A, 1B), wherein the frame (reference numeral 140) is overmoulded to the stator assembly (see figures 1A, 1B). Kim et al. however do not specifically disclose the frame comprising a plurality of turbulators. Having a plurality of turbulators for the frame is a known skill in the art as exhibited by Lau et al. (reference numeral 42, see figures 1-5). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the turbulators as disclosed by Lau et al. for the frame of Kim et al. for dissipating heat from the device (see Lau et al.'s Abstract). For claim 2, Kim et al. in view of Lau et al. disclose the claimed invention except for the turbulators being formed during a process of over-moulding the frame to the stator assembly. Lau et al. further disclose the turbulators (reference numeral 42) being formed on the molding (reference numeral 40, see figures 1-5, and paragraph [0027]), which when applied to the frame of Kim et al. in view of Lau et al. would disclose the turbulators being formed during a process of over-moulding the frame to the stator assembly. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the turbulators on the molding as disclosed by Lau et al. so that the turbulators are formed during a process of over-moulding the frame to the stator assembly of Kim et al. in view of Lau et al. for dissipating heat from the device (see Lau et al.'s Abstract). For claim 19, the invention of Kim et al. in view of Lau et al. disclose the structure of the claimed invention as explained above for claim 1, and applying this invention to an apparatus such as a vacuum cleaner only recites the intended use of the claimed invention, which does not result in a structural difference between the claimed invention and the prior art. Claim(s) 3-5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. in view of Lau et al. as applied to claim 1 above, and further in view of Satoshi (Foreign Patent Document No.: GB 2553242 A). For claim 3, Kim et al. disclose the stator assembly comprising a plurality of stator core sub-assemblies (reference numerals 100a, 100b, 100c, figures 1A, 1B), each stator core comprising a back (reference numerals 110a, 110b, 110c) and first and second arms (reference numerals 120a, 120b, 120c) extending from the back (see figures 1A, 1B). Kim et al. in view of Lau et al. however do not specifically disclose a bobbin attached to the stator core, and a winding wound about the bobbin. Satoshi discloses a bobbin (reference numeral 5) attached to the stator core (reference numeral 32, figure 1), with the winding (reference numerals 41b, 41c, 42b, 42c) wound about the bobbin (see figure 1). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the bobbin with the winding wound on the bobbin as disclosed by Satoshi for the stator core of Kim et al. in view of Lau et al. for predictably providing desirable configuration for facilitating the stator assembly of the device. For claim 4, Kim et al. disclose the frame (reference numeral 140) being overmoulded to stator assembly such that the back of the first and second arms (reference numerals 120a, 120b, 120c) of each stator core is exposed through the frame (i.e. outer periphery of back 110a, 110b, 110c and inner periphery of first and second arms 120a, 120b, 120c being exposed through the frame 140, see figures 1A, 1B). For claim 5, Kim et al. in view of Lau et al. and Satoshi disclose the claimed invention except for the plurality of turbulators overlying the backs of the stator cores. Lau et al. further disclose the plurality of turbulators (reference numeral 42) overlying the backs of the stator cores (reference numeral 12, see figure 5), and it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the turbulators overlying the backs of the stator cores as disclosed by Lau et al. for the turbulators of Kim et al. in view of Lau et al. and Satoshi for dissipating heat from the device (see Lau et al.'s Abstract). Claim(s) 6 and 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. in view of Lau et al. as applied to claim 1 above, and further in view of Boughtwood (WIPO Document No.: WO 97/40569 A1). For claim 6, Kim et al. in view of Lau et al. disclose the claimed invention except for the plurality of turbulators being obliquely angled relative to an axis substantially parallel to a central longitudinal axis of the brushless motor. Having the turbulators be obliquely angled to an axis is a known skill as exhibited by Boughtwood (reference numeral 10, see figures 6A, 7A), and it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the obliquely angled configuration as disclosed by Boughtwood for the turbulators of Kim et al. in view of Lau et al. for predictably providing desirable configuration for optimizing heat dissipation for the device. For claim 13, Kim et al. in view of Lau et al. disclose the claimed invention except for the plurality of turbulators comprising a plurality of pairs of turbulators, each pair of turbulators arranged in a generally V-shaped formation. Having pairs of turbulators be arranged in a V-shaped formation is a known skill as exhibited by Boughtwood (reference numeral 10, see figures 6A, 7A), and it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the V-shaped formation for the pair of turbulators as disclosed by Boughtwood for the turbulators of Kim et al. in view of Lau et al. for predictably providing desirable configuration for optimizing heat dissipation for the device. Claim(s) 7-11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. in view of Lau et al. and Boughtwood as applied to claim 6 above, and further in view of Liou (US Patent Application Pub. No.: US 2021/0088123 A1). For claim 7, Kim et al. in view of Lau et al. and Boughtwood disclose the claimed invention except for the plurality of turbulators being angled between 45-75 degrees relative to the axis. Having a particular angle would merely involve adjusting the orientation as disclosed by Liou (reference numerals 100b, 200, see figure 11), and it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to adjust the orientation as disclosed by Liou for the turbulators of Kim et al. in view of Lau et al. and Boughtwood for predictably providing desirable configuration for optimizing heat dissipation for the device. For claim 8, Kim et al. in view of Lau et al., Boughtwood, and Liou disclose the claimed invention except for the plurality of turbulators being angled at around 60 degrees relative to the axis. Having a particular angle would merely involve adjusting the orientation as disclosed by Liou (reference numerals 100b, 200, see figure 11), and it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to adjust the orientation as disclosed by Liou for the turbulators of Kim et al. in view of Lau et al., Boughtwood, and Liou for predictably providing desirable configuration for optimizing heat dissipation for the device. For claim 9, Kim et al. in view of Lau et al. and Boughtwood disclose the claimed invention except for the trailing end of each turbulator being closer to the axis than a leading end of the turbulator. Having ends of the turbulator be closer to an axis would merely involve changing the orientation or size of the turbulator which is a known skill as disclosed by Liou (reference numerals 100b, 200, see figure 11), and it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to adjust the size/orientation as disclosed by Liou for the turbulators of Kim et al. in view of Lau et al. and Boughtwood for predictably providing desirable configuration for optimizing heat dissipation for the device. For claim 10, Kim et al. in view of Lau et al. and Boughtwood disclose the claimed invention except for a pitch to height ratio of each turbulator being in the region of 6:1 to 12:1. Having a particular pitch and height for the turbulator would merely involve changing the orientation or size of the turbulator which is a known skill as disclosed by Liou (reference numerals 100b, 200, see figure 11), and it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to adjust the size/orientation as disclosed by Liou for the turbulators of Kim et al. in view of Lau et al. and Boughtwood for predictably providing desirable configuration for optimizing heat dissipation for the device. For claim 11, Kim et al. in view of Lau et al., Boughtwood, and Liou disclose the claimed invention except for the pitch to height ratio of each turbulator being around 7:1. Having a particular pitch and height for the turbulator would merely involve changing the orientation or size of the turbulator which is a known skill as disclosed by Liou (reference numerals 100b, 200, see figure 11), and it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to adjust the size/orientation as disclosed by Liou for the turbulators of Kim et al. in view of Lau et al., Boughtwood, and Liou for predictably providing desirable configuration for optimizing heat dissipation for the device. Claim(s) 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. in view of Lau et al. as applied to claim 1 above, and further in view of Liou (US Patent Application Pub. No.: US 2021/0088123 A1). For claim 12, Kim et al. in view of Lau et al. disclose the claimed invention except for a height of each turbulator being in the region of 0.3-0.9 mm. Having a particular height for the turbulator would merely involve changing the size of the turbulator which is a known skill as disclosed by Liou (reference numerals 100b, 200, see figure 11), and it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to adjust the size as disclosed by Liou for the turbulators of Kim et al. in view of Lau et al. for predictably providing desirable configuration for optimizing heat dissipation for the device. Claim(s) 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. in view of Lau et al. as applied to claim 1 above, and further in view of Rabbi et al. (US Patent Application Pub. No.: US 2021/0107664 A1). For claim 14, Kim et al. in view of Lau et al. disclose the claimed invention except for the frame comprising a main body having protrusions, each protrusion overlying a respective stator core, and each protrusion comprising a region of increased radius relative to regions of the main body between adjacent stator cores of the stator assembly. Having protrusions for the frame where the protrusions overlay the stator core is a known skill as exhibited by Rabbi et al. which disclose a frame (reference numeral 230, see figures 17-19) having protruding portions (reference numeral 600) that align with a stator core (reference numeral 200, see figures 17-19), which when applied to the frame of Kim et al. in view of Lau et al. would disclose each protrusion comprising a region of increased radius relative to regions of the main body between adjacent stator cores of the stator assembly. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the protrusions as disclosed by Rabbi et al. for the stator core of Kim et al. in view of Lau et al. for predictably providing desirable configuration for optimizing heat dissipation for the device. Claim(s) 15 and 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. in view of Lau et al. as applied to claim 1 above, and further in view of Stafford et al. (Foreign Patent Document No.: GB 2571553 A). For claim 15, Kim et al. in view of Lau et al. disclose the claimed invention except for the frame comprising a plurality of struts, each strut extending from a respective region of the frame overlying a core back to a shroud of the frame. Stafford et al. disclose the frame (reference numeral 14) comprising a plurality of struts (reference numerals 94, 96, 98, 100, see figure 6), each strut (reference numerals 94, 96, 98, 100) extending from a respective region of the frame overlying a core back (i.e. stator cores 16, 18, 20, 22, see figures 5, 7) to a shroud (reference numeral 90) of the frame (see figure 6). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the struts as disclosed by Stafford et al. for the frame of Kim et al. in view of Lau et al. for predictably providing further structural support for the device. For claim 16, Kim et al. in view of Lau et al. and Stafford et al. disclose the claimed invention except for each of the plurality of struts overlying a winding, and a leading end of each strut being substantially aligned with a leading edge of the winding which the strut overlies. Stafford et al. disclose the struts (reference numerals 94, 96, 98, 100) overlying the stator assemblies (reference numerals 94, 96, 98, 100, see figures 5, 7) with each stator assembly having a winding (reference numeral 72, figure 5) which are aligned with the strut (see figures 5, 7), therefore teaching a leading end of each strut being substantially aligned with a leading edge of the winding which the strut overlies. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the struts overlying the winding as disclosed by Stafford et al. for the struts of Kim et al. in view of Lau et al. and Stafford et al. for predictably providing further structural support for the device. Claim(s) 17 and 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. in view of Lau et al. as applied to claim 1 above, and further in view of Ha (US Patent Application Pub. No.: US 2021/0067004 A1). For claim 17, Kim et al. disclose the brushless motor comprising a rotor assembly (reference numeral 200, see figures 1A, 1B), but Kim et al. in view of Lau et al. however do not specifically disclose the frame comprising a plurality of apertures for introducing airflow to the rotor assembly in use. Having apertures for the frame is a known skill as exhibited by Ha (reference numeral 112a, see figure 4), and it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the apertures as disclosed by Ha for the frame of Kim et al. in view of Lau et al. for predictably providing desirable cooling configurations for the device. For claim 18, Kim et al. in view of Lau et al. and Ha disclose the claimed invention except for the frame comprising a plurality of grooves formed in an outer surface of the frame for guiding airflow into the plurality of apertures. Forming grooves for the apertures is a known skill as exhibited by Ha (reference numeral 112a, see figure 4), and it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the grooves as disclosed by Ha for the apertures of Kim et al. in view of Lau et al. and Ha for predictably providing desirable cooling configurations for the device. Conclusion The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. The following references disclose embodiments of housing/stator configurations: US 11174937 B2 (Liou; Joe J.), US 11059599 B2 (Rabbi; Sheikh Fazle et al.), US 20200006997 A1 (KIM; Taekyung et al.). Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALEX W MOK whose telephone number is (571)272-9084. The examiner can normally be reached 8am-4pm. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Seye Iwarere can be reached at (571) 270-5112. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /ALEX W MOK/Primary Examiner, Art Unit 2834
Read full office action

Prosecution Timeline

Jan 11, 2024
Application Filed
Jan 03, 2026
Non-Final Rejection — §103, §DP (current)

Precedent Cases

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
74%
Grant Probability
95%
With Interview (+21.2%)
2y 11m
Median Time to Grant
Low
PTA Risk
Based on 1114 resolved cases by this examiner. Grant probability derived from career allow rate.

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